<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Title</title>
    <script>
        "use strict";//利用严格检查模式
        var map = new Map([["tom", 10], ["jack", 20], ['young', 30]]);
        var name = map.get('tom');//通过key获得值
        alert(name);
        map.set("girl", 40);//添加修改元素
        map.delete("young");//删除
        //set就是无序不重复的集合
        var set = new Set([1, 2, 3, 4, 5]);
        set.add(6);
        console.log(set.has(7));
        set.delete(1)
    </script>
</head>
<body>

</body>
</html>